Leche de tigre, literally tiger's milk, is the citrus-based, spicy marinade used to cure the fish in classic Peruvian ceviche. Leche de tigre, or tiger's milk, is the Peruvian term for the citrus-based marinade that cures the seafood in a ceviche. Also known as leche de pantera, this leftover fish runoff usually contains lime juice, sliced onion, chiles, salt, and pepper along with a bit of fish juice. The milky liquid is sometimes made on its own with fish stock. There are numerous variations of leche de tigre, but each drink is characterized by its blend of numerous flavors: spicy, acidic, savory, creamy, and fresh.